To more fully elaborate the clinical, histochemical, biochemical, ultrastructural and immunologic abnormalities of patients with the various myopathies. To further subclassify patients in each category using those parameters. To seek pathogenic mechanisms using a variety of different techniques, including tissue culture and the one listed above, applied to the patients' body fluids and tissues, especially to the muscle biopsy specimens. To treat myopathic disorders by different methods in order to learn which is most effective within each disease category. To produce animal models of pathogenic phenomena.